com32/include/byteswap.h

   1 #ifndef _BYTESWAP_H
   2 #define _BYTESWAP_H
   3
   4 #include <stdint.h>
   5 #include <klibc/endian.h>
   6 #include <klibc/compiler.h>
   7
   8 /* This assumes an i386 platform */
   9
  10 #define __bswap_16_macro(v) ((uint16_t)                                 \
  11                              (((uint16_t)(v) << 8) |                    \
  12                               ((uint16_t)(v) >> 8)))
  13
  14 static inline __constfunc uint16_t __bswap_16(uint16_t v)
  15 {
  16     return __bswap_16_macro(v);
  17 }
  18
  19 #define bswap_16(x) (__builtin_constant_p(x) ?                          \
  20                         __bswap_16_macro(x) : __bswap_16(x))
  21
  22 #define __bswap_32_macro(v) ((uint32_t)                                 \
  23                              ((((uint32_t)(v) & 0x000000ff) << 24) |    \
  24                               (((uint32_t)(v) & 0x0000ff00) << 8)  |    \
  25                              (((uint32_t)(v) & 0x00ff0000) >> 8)  |     \
  26                               (((uint32_t)(v) & 0xff000000) >> 24)))
  27
  28 static inline __constfunc uint32_t __bswap_32(uint32_t v)
  29 {
  30 #if defined(__x86_64__)
  31     asm("bswap %0" : "+r" (v));
  32 #elif defined(__i386__)
  33     asm("xchgb %h0,%b0 ; roll $16,%0 ; xchgb %h0,%b0"
  34         : "+q" (v));
  35 #else
  36     v = __bswap_32_macro(v);
  37 #endif
  38     return v;
  39 }
  40
  41 #define bswap_32(x) (__builtin_constant_p(x) ?                          \
  42                          __bswap_32_macro(x) : __bswap_32(x))
  43
  44
  45 #define __bswap_64_macro(v) ((uint64_t)                                 \
  46     (((uint64_t)__bswap_32_macro((uint32_t)(v)) << 32) |                \
  47      (__bswap_32_macro((uint32_t)((uint64_t)(v) >> 32)))))
  48
  49 static inline __constfunc uint64_t __bswap_64(uint64_t v)
  50 {
  51 #if defined(__x86_64__)
  52     asm("bswap %0" : "+r" (v));
  53 #else
  54     v = ((uint64_t)__bswap_32(v) << 32) | __bswap_32(v >> 32);
  55 #endif
  56     return v;
  57 }
  58
  59 #define bswap_64(x) (__builtin_constant_p(x) ?                          \
  60                         __bswap_64_macro(x) :  __bswap_64(x))
  61
  62 /* This is generic */
  63
  64 #if __BYTE_ORDER == __LITTLE_ENDIAN
  65
  66 #define be16_to_cpu(x) bswap_16(x)
  67 #define cpu_to_be16(x) bswap_16(x)
  68 #define be32_to_cpu(x) bswap_32(x)
  69 #define cpu_to_be32(x) bswap_32(x)
  70 #define be64_to_cpu(x) bswap_64(x)
  71 #define cpu_to_be64(x) bswap_64(x)
  72
  73 #define le16_to_cpu(x) (x)
  74 #define cpu_to_le16(x) (x)
  75 #define le32_to_cpu(x) (x)
  76 #define cpu_to_le32(x) (x)
  77 #define le64_to_cpu(x) (x)
  78 #define cpu_to_le64(x) (x)
  79
  80 #elif __BYTE_ORDER == __BIG_ENDIAN
  81
  82 #define le16_to_cpu(x) bswap_16(x)
  83 #define cpu_to_le16(x) bswap_16(x)
  84 #define le32_to_cpu(x) bswap_32(x)
  85 #define cpu_to_le32(x) bswap_32(x)
  86 #define le64_to_cpu(x) bswap_64(x)
  87 #define cpu_to_le64(x) bswap_64(x)
  88
  89 #define be16_to_cpu(x) (x)
  90 #define cpu_to_be16(x) (x)
  91 #define be32_to_cpu(x) (x)
  92 #define cpu_to_be32(x) (x)
  93 #define be64_to_cpu(x) (x)
  94 #define cpu_to_be64(x) (x)
  95
  96 #else
  97
  98 #error "Unknown byte order!"
  99
 100 #endif
 101
 102 typedef struct { uint16_t x; } __attribute__((packed)) __ua_uint16_t;
 103 typedef struct { uint32_t x; } __attribute__((packed)) __ua_uint32_t;
 104 typedef struct { uint64_t x; } __attribute__((packed)) __ua_uint64_t;
 105
 106 /* These are guaranteed to support unaligned accesses */
 107 static inline uint16_t get_le16(const uint16_t *p)
 108 {
 109     const __ua_uint16_t *up = (const __ua_uint16_t *)p;
 110     return le16_to_cpu(up->x);
 111 }
 112
 113 static inline uint32_t get_le32(const uint32_t *p)
 114 {
 115     const __ua_uint32_t *up = (const __ua_uint32_t *)p;
 116     return le32_to_cpu(up->x);
 117 }
 118
 119 static inline uint64_t get_le64(const uint64_t *p)
 120 {
 121     const __ua_uint64_t *up = (const __ua_uint64_t *)p;
 122     return le64_to_cpu(up->x);
 123 }
 124
 125 static inline uint16_t get_be16(const uint16_t *p)
 126 {
 127     const __ua_uint16_t *up = (const __ua_uint16_t *)p;
 128     return be16_to_cpu(up->x);
 129 }
 130
 131 static inline uint32_t get_be32(const uint32_t *p)
 132 {
 133     const __ua_uint32_t *up = (const __ua_uint32_t *)p;
 134     return be32_to_cpu(up->x);
 135 }
 136
 137 static inline uint64_t get_be64(const uint64_t *p)
 138 {
 139     const __ua_uint64_t *up = (const __ua_uint64_t *)p;
 140     return be64_to_cpu(up->x);
 141 }
 142
 143 static inline void put_le16(uint16_t v, uint16_t *p)
 144 {
 145     __ua_uint16_t *up = (__ua_uint16_t *)p;
 146     up->x = cpu_to_le16(v);
 147 }
 148
 149 static inline void put_le32(uint32_t v, uint32_t *p)
 150 {
 151     __ua_uint32_t *up = (__ua_uint32_t *)p;
 152     up->x = cpu_to_le32(v);
 153 }
 154
 155 static inline void put_le64(uint64_t v, uint64_t *p)
 156 {
 157     __ua_uint64_t *up = (__ua_uint64_t *)p;
 158     up->x = cpu_to_le64(v);
 159 }
 160
 161 static inline void put_be16(uint16_t v, uint16_t *p)
 162 {
 163     __ua_uint16_t *up = (__ua_uint16_t *)p;
 164     up->x = cpu_to_be16(v);
 165 }
 166
 167 static inline void put_be32(uint32_t v, uint32_t *p)
 168 {
 169     __ua_uint32_t *up = (__ua_uint32_t *)p;
 170     up->x = cpu_to_be32(v);
 171 }
 172
 173 static inline void put_be64(uint64_t v, uint64_t *p)
 174 {
 175     __ua_uint64_t *up = (__ua_uint64_t *)p;
 176     up->x = cpu_to_be64(v);
 177 }
 178
 179 #endif /* _BYTESWAP_H */
 180